Hand exerciser



FIG. 1 is a perspective view of a hand exerciser, showing my new design, the broken line showing of the hand is for illustrative purposes only, and forms no part of the claimed design;

FIG. 2 is a side elevational view thereof, the opposite side being identical thereto;

FIG. 3 is a front view thereof, the rear view being identical thereto; and,

FIG. 4 is a top plan view thereof; the bottom being identical thereto. 

The ornamental design for a hand exerciser, as shown and described. 